Support device for liquid crystal flat screen

ABSTRACT

Support device for a liquid crystal flat screen ( 12 ), in particular for computer workstations, of the type including an arm ( 14 ) suitable for connection to a carrying structure ( 16 ), and an articulating mechanism ( 18 ) interposed between the arm and the screen. The carrying structure includes a stirrup ( 20 ) with two horizontally spaced walls ( 104, 106 ) and respectively provided with two aligned apertures ( 108, 110 ) defining a horizontal passage ( 32 ) with a given axis (XX) capable of being passed through by the cantilevered arm ( 14 ).

[0001] The invention relates to office equipment, in particular computerequipment.

[0002] More particularly it relates to a support device for a liquidcrystal flat screen, in particular for computer workstations.

[0003] It is known that liquid crystal flat screens are used more andmore in computer workstations, in particular those intended for bankingestablishments, trading rooms and the like.

[0004] In fact, owing to their small space requirement and the visualconvenience with which they provide the user, these flat screensadvantageously replace the traditional cathode ray tube screens.

[0005] Support devices for liquid crystal flat screens are already knowncomprising an arm, and an articulating mechanism interposed between thearm and the screen.

[0006] In the known devices of this type, the arm is generally connectedto a carrying structure and is generally composed of a plurality ofelements articulated to one another. This arm made of a plurality ofelements is often bulky and requires the use of a strong carryingstructure which also takes up space on the workstation where it isplaced.

[0007] Moreover, the arm is generally connected in a non-detachablemanner to the carrying structure and this means that the flat screen hasto be mounted, in situ, directly on the articulating mechanism carriedby the arm. Taking into account the particular constraints of eachworkstation, this installation is generally carried out “blind” whichposes a number of practical problems.

[0008] Moreover, these support devices are difficult to adjust or easilylose their adjusted position.

[0009] Finally, these known devices are generally poorly adapted todouble workstations which are often found in banking establishments,trading rooms, and similar in which two desks are found disposed facingone another and which are each intended to receive their own equipment.

[0010] In any case, these known support devices are bulky and thereforeincompatible with liquid crystal flat screens.

[0011] In fact the benefit obtained with respect to bulkiness with aflat screen is generally lost, at least partially, due to the bulkinessof the support device itself.

[0012] The object of the invention is in particular to overcome theabove-mentioned drawbacks.

[0013] In particular it aims to provide a support device for a liquidcrystal flat screen which has a simple structure and is easy to install.

[0014] It also aims to provide a support device of this type which doesnot require a large amount of space on the workstation on which thedevice is installed.

[0015] It also aims to provide a support device of this type which iscompatible with a large range of liquid crystal screens.

[0016] It is also an object of the invention to obtain a support deviceof this type which allows easy adjustment of the flat screen in amultiplicity of possible positions and without the flat screen thenbeing able to lose its adjusted position.

[0017] For this purpose the invention proposes a support device of thetype defined at the outset in which the carrying structure comprises astirrup having two horizontally spaced walls and respectively providedwith two aligned apertures defining a passage of given axis adapted forthe passage of the cantilevered arm.

[0018] Owing to the cantilever of the screen and the arm a moment isproduced in stirrup causing the arm to be wedged in the two apertures ofthe stirrup. The arm thus constitutes an adjustable bracket at the endof which the screen is mounted.

[0019] In a preferred embodiment of the invention, the arm comprises atube with a circular cylindrical wall, while at least one of theapertures comprises a V-shaped end to ensure the translatory androtational locking of the tube, by a wedging effect.

[0020] This wedging prevents the tube from rotating on itself and locksit with respect to rotation. The tube can therefore be placed in thestirrup in a given axial and angular position and be kept in thisposition by a simple locking effect owing to the particular form of atleast one of the aligned apertures.

[0021] Moreover, as the arm is connected in a non-detachable manner tothe stirrup, the stirrup allows the arm to be initially fixed to thescreen by the articulating mechanism, and then allows the introductionof-the arm into-the passage defined by the stirrup.

[0022] Mounting of the flat screen is thus facilitated. In fact, incontrast to the known devices where the securing point is situateddirectly on the back of the screen and requires blind mounting, thedevice of the invention allows permanent viewing of the fixing pointduring mounting.

[0023] Preferably, the two apertures of the stirrup each have a V-shapedend, and these two V-shaped ends are arranged head to tail, the onedirected upwardly and the other downwardly.

[0024] In a preferred embodiment of the invention each of these V-shapedends is delimited by two straight edges forming a selected angle betweenthem and being joined to an edge in the shape of an arc of a circlehaving a diameter which is slightly greater than the diameter of thetube.

[0025] The above-mentioned angle is advantageously selected to bebetween 50° and 70°, and preferably equal to 60°.

[0026] The two walls of the stirrup are preferably respectively part oftwo shells which are joined together.

[0027] According to a further characteristic of the invention, thestirrup comprises a vertical cylindrical passage with an axis which issubstantially orthogonal to the horizontal passage, said verticalpassage being able to be passed through by a vertical cylindrical polewhich is part of the carrying structure, so as to allow theimmobilisation of the stirrup in a defined axial and angular positionrelative to the pole, by means of a cantilever wedging effect.

[0028] It is therefore possible to easily displace the stirrup along thepole and to place it at the desired level and orientation, the stirrupautomatically resting in position owing to the overhanging effect on thepole. Definitive locking can, if necessary, be produced for safetyreasons, as will be seen hereinafter.

[0029] Each of the above-mentioned shells preferably comprises an upperfolded edge provided with an upper notch in the shape of an arc of acircle capable of facing a similar upper notch of the other shell, and alower folded edge provided with a lower notch in the shape of an arc ofa circle capable of facing a similar lower notch of the other shell.

[0030] The stirrup preferably also comprises a screw-type locking memberto lock the stirrup in this defined axial and angular position.

[0031] According to a further characteristic of the invention, the armis a telescopic tube which comprises a first cylindrical portion adaptedto slide in the horizontal passage of the stirrup and the secondcylindrical portion adapted to slide in the first portion and supportingthe ball.

[0032] The first portion and the second portion of the tube preferablyeach have a circular cylindrical shape and comprise mutual rotationallocking means.

[0033] In the description which follows, which is given only by way ofexample, reference is made to the accompanying drawings, in which:

[0034]FIG. 1 is a perspective view of a support device for a liquidcrystal flat screen according to the invention;

[0035]FIG. 2 is a sectional view, viewed in the axis of the arm in theshape of a tube, of the device of FIG. 1;

[0036]FIG. 3 is a front view of the stirrup, which is a part of thecarrying structure;

[0037]FIG. 4 is a sectional view of the device, the tube being shown inthe telescoped position;

[0038] FIGS. 5 to 7 are part sectional views similar to FIG. 2 showingthree different positions of the ball;

[0039]FIG. 8 is a front view of a shell which is part of the stirrup ofthe device of the invention;

[0040]FIG. 9 is a plan view corresponding to FIG. 8; and

[0041]FIG. 10 is an axial sectional view of a ball in a differentembodiment of the invention.

[0042] Reference is firstly made to FIG. 1 which shows a device 10intended to support a flat screen 12 of the liquid crystal type such asthose used, for example in computer workstations.

[0043] The device 10 comprises an arm 14, forming a bracket, disposed ina position which is substantially horizontal being supported by acarrying structure 16. An articulating mechanism 18 is interposedbetween the arm 14 and the screen 12.

[0044] The carrying structure 16 comprises a stirrup 20, also called ashoe, which can slide vertically (double arrow F1) along a vertical pole22 produced here in the form of a tube with a circular cylindrical wall.The pole 22 comprises a footing 24 adapted to being fixed, preferably inan adjustable manner, on a workstation, for example a computer desk.

[0045] In the example, the position of the footing 24 can be adjustedalong a horizontal rail 26 (shown schematically) provided on saidcomputer workstation.

[0046] The arm 14 is produced here in the form of a telescopic tubewhich comprises a first tubular portion 28, in the example with acircular cylindrical form, and a second tubular portion 30, also of acircular cylindrical form, capable of sliding inside the tubular portion28.

[0047] The tubular portion 28 is adapted to slide axially and rotatefreely in a horizontal passage 32 of the axis XX defined by the stirrup20. Thus, the tubular portion 28 can be adjusted in a given axial andangular position with respect to the stirrup 20. The stirrup is alsoadjustable in a given angular position with respect to the pole 22 asshown by the arrow F2.

[0048] In addition, the tubular portion 30 can be axially adjusted withrespect to the portion 28 which allows the distance between the screen12 and the stirrup to be modified in a large range taking into accountthe telescopic character of the arm 14.

[0049] Preferably the tubular portions 28 and 30 comprise mutualrotational locking means to prevent the tubular portion 30 from rotatingwith respect to the tubular portion 28 under the action of a torqueproduced by the screen 12 when it is in an inclined cantilever position.

[0050] These mutual locking means are advantageously of the groove type,shown schematically at 34 in FIG. 1.

[0051] The articulating mechanism 18 will now be described withparticular reference to FIGS. 2 and 4. In FIG. 2, the arm 14 (telescopictube) is shown in the opened-out position, while in FIG. 4 this arm isshown in the retracted position.

[0052] The articulating mechanism 18 comprises a ball 36 which has ahemispherical surface 38 with a centre C (FIG. 4). The ball 36 isextended by four radial lugs 40 which can better be seen in FIG. 1.These four lugs are disposed at 90° to one another and each comprise twobores 42 to allow the ball 36 to be fixed on a rear face 44 of thescreen. Said face is provided with four appropriate bores (not shown) tothe VESA standard. The existence of two bores 42 on each of the lugs 40allows the ball to be adapted to screens of different sizes.

[0053] The ball 36 itself is received in an internal housing 48 definedby the cage 46. However, the interior surface of the cage does notconstitute a surface equivalent to the hemispherical surface 38. On thecontrary, the cage only comes into contact with the hemisphericalsurface 38 by an internal annular edge 50 which thus forms an annularand narrow contact surface. The cage 46 is extended by a sleeve 52 whichdefines an axial cylindrical passage 54.

[0054] The tubular portion 30 of the arm 14 comprises a first end 56which adapts around the sleeve 52 and a second end 58 which receives onthe interior a support 60, of which the structure will be describedhereinafter.

[0055] The ball 18 and the cage 46 are each formed from a material withhigh mechanical strength and a high coefficient of friction. In thisrespect it is advantageous for the ball and the cage to each be formedfrom an appropriate plastics material, and in particular of thepolycarbonate type. The ball 38 and the cage 46 can thus be easilyproduced by injection moulding of this particular plastics material.

[0056] According to the invention, the device also comprises tractionmeans 62 interposed between the cage and the ball to exert a elasticrestoring force of a selected value which causes the ball 38 to restagainst the annular edge 50 of the cage. Owing to and taking intoaccount the high coefficient of friction of the material used, the balland the cage are elastically biased against one another and this allowsthe ball to be immobilised, in a selected orientation, with respect tothe cage.

[0057] In the embodiment shown, the traction means 62 comprise a tie rod64 which, in the example, is a flexible cable, in particular amulti-strand metal cable. This tie rod 64 passes through the ball andthe cage and comprises a first end stop 66, here of general circularcylindrical form, which rests substantially at the centre C of the ball.

[0058] For this purpose, the ball 38 comprises a cylindrical housing 68serving to receive the stop 66 and opening on a rear face 70 of theball. This housing 68 communicates with a frustoconical passage 74 whichis used for the passage of the tie rod and opens onto the hemisphericalsurface 38 of the ball. This passage 74 has a general conical form andcomprises a narrow aperture 76 which communicates with the housing ofthe stop 68 and a wide aperture 78 of circular form which opens onto thehemispherical surface of the ball.

[0059] The tie rod 64 comprises a second end stop 80 which is receivedin the support 60 outside the cage. For this purpose, the end of the tierod is produced in the form of a threaded portion equipped with anadjusting nut 48 and passed through by a helical spring 84 which restsagainst a support ring 86 which is part of the support 60.

[0060] More particularly, this support 60 comprises a sleeve 88terminated by a collar 90 and of which the base consists of theabove-mentioned support ring 86. The spring 84 is disposed between twowashers: one washer 92 situated against the nut 82 and one washer 94situated against the support ring 86.

[0061] It will be understood that the axial force F3 which is exerted onthe ball and therefore the lateral force F4 exerted against the annularedge 50 can be adjusted (FIG. 4). This adjustment is obtained byjudicious selection of the stiffness spring and by appropriateadjustment of the axial position of the nut 82.

[0062] The combination of this adjustment and the selection of thematerials constituting the ball and the cage allow considerable frictionto be produced between the ball and the cage and this allows the ball tobe immobilised in a selected orientation and this orientation to bemaintained despite the weight exerted by the screen 12.

[0063] It will be noted that the tubular portion 28 of the arm isterminated, on one side, by a ring 95 which slides inside the tubularportion 30 and, on the other side, by a cap 96 of conical shape. Thiscap hides the access to the adjusting nut and also constitutes a stoppreventing the arm 14 from escaping the stirrup 20.

[0064] As can be seen in FIGS. 5 to 7, the ball 36 (therefore the screen12) may adopt an infinity of orientations. In any case, the tractionforce exerted on the ball is applied substantially to the centre thereofand in the axis of the arm. Taking into account the frustoconical formof the tie rod passage 74 the ball may have a large range of movement.This allows an infinity of adjusting positions or orientations, incombination with the fact that the arm 14 is itself telescopic and thatit is carried by a stirrup which is adjustable with respect to heightand orientation with respect to the pole 22.

[0065] The structure of the stirrup 20 will now be described withparticular reference to FIGS. 1 to 3 and 8 and 9.

[0066] The stirrup 20 comprises two portions or shells 100 and 102 whichare generally similar, arranged on either side of the pole 22 and joinedtogether, the portion 100 being situated on the side facing the screen12 and the portion 102 on the opposite side.

[0067] The shells 100 and 102 have respective walls 104 and 106 spacedhorizontally and equipped respectively with two aligned apertures 108and 110 which define the above-mentioned horizontal passage 32 of theaxis XX.

[0068] The two apertures 108 and 110 each have a V-shaped end, inparticular 112 and 114 respectively, these two ends being disposed headto tail. The end 112 of the aperture 108 is directed downwardly, whilethe end 114 of the aperture 110 is directed upwardly (see FIG. 1). Eachof these ends, for example the end 112 is delimited by two straightedges 116 forming between them a selected angle A, typically between 50°and 70°, and 60° in the example (FIG. 8). These two straight edges 116join at an edge 118 in an arc of a circle of which the diameter isslightly greater than the diameter of the tubular portion 28 of the arm.

[0069] The straight edges 116 of the aperture 108 do not form a real Vto the extent that they are joined together at a transverse edge 120.

[0070] Thus, the tubular portion 28 of the arm can slide axially in thepassage 32 and be immobilised in a given axial position and a givenangular position. Moreover, the tubular portion 30 can be displacedsimply by axial sliding, with respect to the tubular portion 28, toprovide additional adjustment of the screen as already indicated.

[0071] The tubular portion 28 is thus locked in position with respect tothe stirrup by the cooperation of the tubular wall of this portion 28with the two V-shaped ends which are oriented head to tail.

[0072] In a simplified version it is possible to provide that only oneof the two apertures comprises a V-shaped end. Each of the shells, forexample the shell 100, comprises an upper folded edge 122 provided withan upper notch 124 in the shape of an arc of a circle adapted to face asimilar upper notch of the other shell, and a lower folded edge 126equipped with a lower notch 128 in the shape of an arc of a circle toface a similar lower notch of the other shell.

[0073] Thus, when the shells are disposed facing one another, the twofacing upper notches and the two facing lower notches contribute todefining a vertical cylindrical passage 130 which admits an axis YYwhich is substantially orthogonal to the axis XX of the horizontalpassage 32 (FIG. 1). This vertical passage is designed to be passedthrough by the vertical cylindrical pole 22 described above.

[0074] The shells 100 and 102 are generally similar and areadvantageously produced by moulding of a metal material.

[0075] They are kept together by means of two screws 132 (FIG. 3) whichpass through two circular apertures 134 of the shell 100 and cooperatewith similar threaded passages of the shell 102.

[0076] The stirrup 20 also comprises a locking member 136 of the screwtype for screwing the stirrup in a defined angular and axial position.This member 136 comprises a button 138 extended by a threaded rod 130which passes through an aperture 142 of the shell 100 and cooperateswith a threaded passage facing the shell 102. It should be noted thatowing to the cantilever force exerted by the weight of the arm and ofthe screen, the stirrup 100 can be immobilised in an axial and angularposition selected with respect to the pole 22, by the simple effect ofwedging. The locking member 136 simply constitutes a safety device forlocking the stirrup in a selected position relative to the pole.

[0077] The ball 38 of FIG. 10 differs from that described above by thefact that it is hollowed instead of being solid. In fact it comprises arecess 144 which opens onto the rear face 70. This lightens the ball andfacilitates its production by moulding without comprising its mechanicalstrength taking into account the material used.

[0078] A device of simple structure, which is not very bulky, allowingan infinity of possible adjustments to be made is thus obtained for aliquid crystal flat screen. The user easily adjusts the screen by theacting directly on the screen itself to bring it into the desiredposition.

[0079] The device can thus be easily installed on a workstation, inparticular a computer desk.

[0080] The invention is not limited to the embodiments described aboveby way of example and numerous variations and possible. It will beunderstood in particular that the articulating mechanism can be usedwith different types of arms, produced in one or more parts.

1. Support device for a liquid crystal flat screen (12), in particularfor computer workstations, of the type comprising an arm (14) suitablefor connection to a carrying structure (16), and an articulatingmechanism (18) interposed between the arm and the screen, characterisedin that the carrying structure comprises a stirrup (20) with twohorizontally spaced walls (104, 106) and respectively provided with twoaligned apertures (108, 110) defining a horizontal passage (32) with agiven axis (XX) capable of being passed through by the cantilevered arm(14).
 2. Device according to claim 1, characterised in that the armcomprises a tube (28) with a circular cylindrical wall and in that atleast one of the apertures (108, 110) comprises a V-shaped end to ensurethe translatory and rotational locking of the tube by a wedging effect.3. Device according to claim 2, characterised in that the two apertures(108, 110) of the stirrup (20) each have a V-shaped end (112, 114) andin that these two V-shaped ends are arranged head to tail, the onedirected upwardly and the other downwardly.
 4. Device according toeither of claims 2 or 3, characterised in that each of the V-shaped endsis delimited by two straight edges (116) forming a selected angle (A)between them and being joined to an edge in the shape of an arc of acircle (118) with a diameter slightly greater than the diameter of thetube.
 5. Device according to claim 4, characterised in that the selectedangle (A) is between 50° and 70° and preferably equal to 60°.
 6. Deviceaccording to any one of claims 1 to 5, characterised in that the twowalls (104, 106) of the stirrup are respectively part of two shells(100, 102) which are joined together.
 7. Device according to any one ofclaims 1 to 6, characterised in that the stirrup comprises a verticalcylindrical passage (130) having an axis (YY) which is substantiallyorthogonal to the axis (XX) of the horizontal passage (32), saidvertical passage being provided to be passed through by a verticalcylindrical pole (22) which is part of the carrying structure, so as toallow the immobilisation of the stirrup in a defined axial and angularposition relative to the pole (22) by a cantilever wedging effect. 8.Device according to claims 6 and 7, taken together, characterised inthat each of the shells (100, 102) comprises an upper folded edge (122)provided with an upper notch (124) in the shape of an arc of a circlecapable of facing a similar upper notch of the other shell, and a lowerfolded edge (126) provided with a lower notch (128) in the shape of anarc of a circle capable of facing a similar lower notch of the othershell.
 9. Device according to either of claims 7 and 8, characterised inthat the stirrup (20) also comprises a screw-type locking member (136)to lock the stirrup in this defined axial and angular position. 10.Device according to any one of claims 1 to 9, characterised in that thearm is a telescopic tube (14) which comprises a first cylindricalportion (28) capable of sliding in the horizontal passage (32) of thestirrup (20) and a second cylindrical portion (30) capable of sliding inthe first cylindrical portion (28) and supporting the ball (36). 11.Device according to claim 10, characterised in that the first portion(28) and the second portion (30) of the tube each have a circularcylindrical shape and comprise mutual rotational locking means (34).